Sinker actuating mechanism for knitting machines



June 14, 1949. 2,473,355

.siNKER ACTUATING MECHANISM FOR KNITTING MACHINES Filed Jan. 3, 1948 E. .J. BERGER ET AL 2 Sheec s-Sheet 1 INVENTORS. Emmi. Bezyez & Howazflii W215i,

WITNESSES A TTORNEYS.

Patented June 14, 19 49 SINKER ACTUATING MECHANISM FOR KNITTING MACHINES Emil J. Berger and Howard K. West, Lansdale Pa., assignors to Dexdale Hosiery Mills, Lansdale, Pa., a corporation of Pennsylvania Application January 3, 1948, Serial No. 408

3 Claims.

This invention relates to sinker actuating mechanism for knitting machines, particularly straight knitting machines of the Cotton type which are commonly used in the commercial production of fashioned stocking blanks and the like.

In such knitting machines, the knitting yarn is kinked between needles by slide sinkers which are actuated, through the medium of individually associated jacks, by reciprocated slur cocks having cam surfaces complementally sloped rearward from a center point for alternate operation upon the jacks during traverse of the slur cocks in opposite directions. The action of the slur cock as ordinarily constructed, is often attended by recession or slap back of the sinkers immediately upon passage of the center point of the slur cocks beyond the corresponding jacks in either direction of traverse, as a consequence of which the butts of jacks so displaced are disaligned with the butts of others, especialy incident to operation of the knitting machines at high speeds. The usual catch bars of the machines whereby the sinkers are retracted after they have sunk the yarns, are accordingly prevented from descending over and engaging the sinker butts with resultant mal operation of the machines and attendant damage to the parts.

The chief aim of our invention is to overcome the difficulty just referred to which objective we achieve as hereinafter more fully disclosed, by associating with the slur cocks, of supplemental reversible cam elements affording as the slur cocks travel in opposite directions, cam surfaces which trail the center points of the slur cocks and thereby restrain one or more jacks immediately in the wake of said center points in passing and thus prevent the undesirable back slap f the corresponding sinkers.

Other objects and advantages will appear from the following detailed description of the attached drawings, wherein Fig. 1 is a fragmentary broken out view showing in top plan, the sinker actuating mechanism of a straight knitting machine conveniently embodying our invention.

Fig. 2 is a transverse section taken as indicated by the angled arrows II1I in Fig. 1.

Figs. 3 and 4 are plan views like Fig. l with the parts differently positioned.

Fig. 5 is a fragmentary detail view in transverse section taken as indicated by the angled arrows VV in Fig. 4.

Figs. 6 and 7 are perspective views respectively of the slur cock of the machine as modified by us, and the associated supplemental cam element hereinbefore referred to.

Referring more specifically to the drawing, the numerals ill and H designate the sinkers and dividers of the knitting machine, the same being arranged in alternation in the transverse guide grooves of the sinker head l2 for endwise sliding movement relative to needles IS in the usual and well known manner. Also as ordinarily, the sinkers it are moved outwardly by individually associated jacks ['5 which are independently fulcrumed on a fixed rod [6 and actuated from behind by a slur cock l1. As usual, the slur cock I! has formed with receding cam surfaces 1) and c which are complementally sloped with respect to its center point a. By means of two screws I8, the slur cock I! is secured to a carriage i the form of a block l9 which is constrained to travel back and forth on a fixed guide rail 29 extending longitudinally of the machine rearward of the sinker head l2. The carriage I9 is reciprocated on the rail through engagement of a pair of spaced upstanding projections 2| thereon with the thread 22a of a rotary spindle 22 in Fig. 2. The usual catch bar for advancing the dividers after projection of the sinkers and for subsequently retracting both the sinkers and the dividers is indicated at 23.

In adapting our invention to a knitting machine such as briefly described up to this point, we have provided a supplemental cam element 25 which is separately illustrated in Fig. '7 and which is pivoted medially on a headed stud 26 set into the slur cock I! at the center of the latter. As shown, the supplemental cam element 25 has a central edge portion d and flanking edge portions e,) which extend outwardly and rearwardly at complemental angles from the opposite ends of said center portion. The swing of the element 25 in opposite directions is limited by engagement of its opposite ends thereof with a longitudinal stop shoulder 21 on the carriage l9, it being yieldingly held in one or the other of its limit positions by a toggle spring 28. As a further aid to this end, the element 25 is provided in its bottom face with two indentations 29 and 30 which are adapted to be alternately engaged by an upwardly spring pressed ball 3| disposed in a socket hole 32 centrally of the slur cock l1 near the front, see Fig. 5. Afilxed to the guide rail 20 adjacent its opposite ends are abutments in the form of inwardly extending fingers 35 and 36 with cam edges 35a, 36a which are arranged to cooperate respectively with studs 31 and 38 on the supplemental cam element 25 to reverse the position of the latter when the slur cock l'1 reaches the limits of its traverse in opposite directions.

Operation During movement of the slur cock II to the right or as indicated by the arrow on the carriage 19 in Fig. l, withzits cam edge 11 leading and active upon the jacks 15 to advance the sinkers, the supplemental cam element oocupies the position in which it is illustrated in Fig. l with its center edge portion d coinciding with said cam edge of the slur cock and with its flanking ca m edge 1 trailing the center point a of the slur cock. The edge f of :the element 25 thus acts upon several jacks immediately :in the wake of the center point a of the slur cock.

Back slap and rebounding of the sinkers I0 is thus prevented with assurance that their butts,

will ;be properly aligned with those of the dividersfor engagement .bythe catch bar 23.

As the carriage completes ritsrightward stroke, the stud 31 on the supplemental cam element 25 encounters the abutment finger 35 as in Fig. 3. As a consequence, .the element 25 is moved clockwise until the spring 28, after having been incidently swung slightly past dead center, snaps it suddenly to the reversed position in which it shown in Fig. 4. As thecarriage i9 is thereupon traversed leftward, the center edge portion dof the supplemental cam element 25 coincides with the now leading cam edge 0 of the slur cock H and the latter edge acting upon the jacks IE to advance the sinkers H1, while the flanking edge eof said element acts upon several :iac-ks immediately in the wake of the center point-a of the slur cock to restrain them and so prevent backslap-of thelcorresponding sinkers. At the endof the leitwardstroke of the carr-iage 19, the supplemental cam element 25 is restored to the position in which it is shown in Fig, 1 upon encounter of the stud 3.8 thereon with the abutment .fingertfi in readiness for the subsequent rightward movement of said carriage. Such reversalsof the supplemental cam element 25 will iolloweach other in succession as the machine continues .in its operation.

Having thus describedour invention, we claim:

1. In sinker actuating mechanism for straight knitting machines, operating jacks individually associated with the sinkers; a reciprocating slur cock with receding cam surfaces complementally sloped relative to a center point .for actuating the jacks to advance the sinkers; an element movably mounted :on'theslur cock and providing stop edges for respectively trailing the center point of :the slur cock as :the latter .is traversed in opposite directions, to temporarily restrain one or more iacksin the Wake of said center point :and thereby prevent back slap of the corresponding sinkers, and fixed abutments respectively at opposite ends of the path of traverse of the slur cook .a'daptedgby cooperation alternatelywith-said element, to position.it so that one of its stop surf-aces trails the .slur cock during traverse in one direction, and its other stop surface trails said cock during traverse in the other direction.

' 2. In sinker actuating mechanism for straight knitting machines, operating jacks individually associated with the sinkers; a reciprocating slur cock with receding cam surfaces complementally sloped relative to a center point, for actuating thejacks to advance thesinkers; aasupplemental cam element medially pivoted on the slur cock, .having a central edge portion and flanking edge portions extending outwardly and rearwardly symmetrically from the opposite ends of the central edge portion; means reciprocating with the slur cock for limiting the swing of the supplemental cam element in opposite directions and-determining operative positions therefor in which the central edge portion coincides with one or the other cam edges of the slur cock depending on the direction of travel of the latter, and in which one or the other of the flanking edge p.ortions,:trails the center point of the slur cock, likewise depending upon the direction of travel, to temporarily restrain one or more jacks immediately in the wake of said center point and thereby prevent back slap of the corresponding sinkers; and means operative upon the supplemental cam element to reverse the position thereof as the slur cock reaches the end of .its traverse in opposite directions.

3. In sinker actuating :mechanismior straight knitting machines, operating jacksindividually associated with the sinkers; a reciprocating slur cock with receding camsurfaces complementally sloped relative to a center point for actuating the jacks to advance-the sinkers; a supplemental cam element medially pivoted on the slur cock having a central edge portion andflanking edge portions extending outwardly and rear-weirdly symmetrically from the opposite ends .of the central edge portion; means reciprocating with the slur cock .for limitingthe swing of the supplemental cam element in opposite directions and determining operative positions therefor in which the central edge portion coincides with one or the other cam edges of theslur cock depending on the direction of travel of the latter, and in which one or the other of the flanking edge portions atrails the center point of the slur cock, likewise depending .upon the direction of travel, to temporarily restrainionezor more jacks immediately in the wake of said :center point and thereby prevent back slap .of the corresponding sinkers; and fixed abutments at the opposite ends of the path of traverse .of the slur cock adapted, by cooperation. alternately with the cam element to reverseits position.

EMIL -J. BERGER. HOWARD K. WEST.

REFERENCES "CITED UNITED STATES PATENTS Name Date 'Weisbecker .Aug. 7, 1945 Number 2,381,376 

